Windows, doors and sliders are generally insulated by stuffing fiberglass insulation, cut to size, between the jamb of a window or door and the frame in which they are to be installed. However, the fiberglass alone does not provide protection against moisture from seeping into the window or door frame making the wood susceptible to wood rot. Sealing to date is accomplished imperfectly by caulking the frame after the window or door is installed. This caulking material itself is subject to deterioration and does not provide a moisture tight barrier. Water leakage, due to improper sealing is the primary cause of wood rot.
Fiberglass and methods for installing fiberglass is also unwieldy, imprecise and unpredictable. For example, first the window or door unit is installed, then the unit is shimmed and then the insulation material is packed around the unit between the jambs and the building frame. As a consequence, because there are currently no standards for installing such products, the quality of the finished installation varies from one installer to another. Once a building is completed and the inside finish work is completed there is not a way for the owner or inspector to determine the quality of installation or insulation.
Although wraps for foundation sills are known, as described in U.S. Pat. No. 5,091,235 to Vergnano, similar to the current materials and methods for sealing and insulating windows and doors, these wraps are not moisture tight and will not over time protect the insulating materials from moisture and thereby render the wood susceptible to wood rot.